Robotic Total Thyroidectomy with Modified Radical Neck Dissection via Unilateral Retroauricular Approach

Abstract

Background

Traditionally, total thyroidectomy was performed through an open transcervical incision; in cases where there was evident nodal metastasis, the conventional surgical approach was to extend the incision into a large single transverse incision to complete the required neck dissection. However, recent innovation in the surgical technique of thyroidectomy has offered the opportunity to reduce the patient’s burden from these prominent surgical scars in the neck. Minimally invasive surgical techniques have been developed and applied by many institutions worldwide, and more recently, various techniques of remote access surgery have been suggested and actively applied.1–6 Since the advent of robotic surgical systems, some have adopted the concept of remote access surgery into developing various robotic thyroidectomy techniques. The more former and widely acknowledged robotic thyroidectomy technique uses a transaxillary (TA) approach, which has been developed by Chung et al. in Korea.7,8 This particular technique has some limitations in the sense that accessing the lymph nodes of the central compartment is troublesome. Terris et al. realized some shortcomings of robotic TA thyroidectomy, especially in their patients in the United States, and developed and reported the feasibility of robotic facelift thyroidectomy.9–13 In cases of thyroid carcinomas with lateral neck node metastases, most abandoned the concept of minimally invasive or remote access surgery and safely adopted conventional open surgical methods to remove the tumor burden. However, Chung et al. have attempted to perform concomitant modified radical neck dissection (MRND) after robotic thyroidectomy through the same TA port.14 This type of robot-assisted neck dissection (RAND) had some inherent limitations, due to fact that lymph nodes of the upper neck were difficult to remove. Over the past few years, we have developed a RAND via modified facelift (MFL) or retroauricular (RA) approach and reported the feasibility and safety of this technique.15, 16 Since then, we have actively applied such RAND techniques in various head and neck cancers. In our country, almost all cases of robotic total thyroidectomy utilize the TA approach. According to the reports made by Terris et al., robotic facelift thyroidectomy technique has been solely applied for ipsilateral hemithyroidectomy. For total thyroidectomy, Terris et al. performed the robotic surgery with bilateral RA incisions. Here, we intend to introduce our novel surgical method after successfully attempting simultaneous robotic total thyroidectomy and RAND via a single RA approach without an axillary incision. To our knowledge, this is the first to report in the medical literature.

Methods

We present four cases of our surgical experience since the beginning of 2013. All patients received robotic total thyroidectomy with MRND via single RA port without axillary incision after approval from the institutional review board at Severance Hospital, Yonsei University College of Medicine. The inclusion criteria for this operation were as follows: (1) patients with malignant carcinomas of the thyroid gland with evident cervical lymph node metastasis on preoperative imaging studies which are indicated for surgery; (2) patients with no previous history of treatment for thyroid carcinoma. The exclusion criteria were as follows: (1) patients with recurred thyroid tumors; (2) patients with thyroid carcinomas that showed gross invasion to local structures or extensive extrathyroidal capsular spread; (3) patients with clinically evident neck nodal metastasis with extracapsular spread; (4) patients with past history of neck surgery of any kind. In order to assess the extent of disease, neck ultrasonography with fine needle aspiration, neck CT or MRI and PET-CT were performed as preoperative evaluation. All patients were given full information of the possible treatment options for their thyroid cancer comprising of open transcervical approach and robotic surgery via RA approach, including the advantages and disadvantages of each treatment choice and provided written, informed consents before the surgery. General clinical information of the patients is outlined in Table 1. The skin incision for the operation was designed just like the approach for robotic facelift thyroidectomy by Terris et al. and RAND, which has been first reported by our institution.11 ^, 16 The operation was performed by the following sequence. Initially, the skin-subplatysmal flap was elevated after making the skin incision to create sufficient working space. During this process, the elevated skin flap was retracted and maintained by retractors held by the assistant. After application of the self-retaining retractor (Sangdosa Inc., Seoul), neck dissection of the upper neck levels was performed under gross vision. Next, RAND through the RA incision was conducted followed by ipsilateral thyroidectomy with central compartment neck dissection (CCND) via the same approach. Finally, contralateral thyroidectomy with CCND was performed via the single RA port. During these steps, the operator is aided by the bedside assistant with long-suction tips to manipulate and direct the dissected specimen to maintain optimal surgical view or to suck out the fume created by the thermocoagulation from the Harmonic shears. The da Vinci robotic surgical system (Intuitive Surgical, Sunnyvale, CA) was introduced via the RA port with a facedown 30° dual-channel endoscopic arm placed in the center, and two instrument arms equipped at either side with 5-mm Maryland forceps and Harmonic curved shears. During the step of robotic contralateral thyroidectomy, a ProGrasp forceps was utilized at times, instead of 5-mm Maryland forceps. The rest of the surgery was completed with the robotic system (see Video for demonstration of operation for patient 2).

Table 1 Clinical characteristics of the patients

Results

For all of the patients, robotic total thyroidectomy with MRND (levels II, III, IV, V) via unilateral RA approach was successfully completed without any significant intraoperative complications or conversion to open or other approach methods. The total operation time was defined as the time from initial skin incision to removal of the final specimen, which was an average 306.1 ± 11.1 min (Table 2). This included the time for skin flap elevation and neck dissection under gross vision (87 ± 2.8 min), setting up the robotic system for RAND (6.8 ± 2.4 min), console time using the robotic system for RAND (59.3 ± 2.2 min), flap elevation for thyroidectomy (11.3 ± 2.5 min), robotic arms docking for ipsilateral thyroidectomy (6.3 ± 2.5 min), console time for ipsilateral thyroidectomy (61.3 ± 2.1 min), robotic arms docking for contralateral thyroidectomy (6.3 ± 2.5 min), and console time for contralateral thyroidectomy (61.8 ± 2.1 min). The working space created from RA incision was sufficient, and manipulations of the robotic instruments through this approach were technically feasible and safe without any mutual collisions throughout the entire operation. It also allowed for an excellent magnified surgical view enabling visualization of important local anatomical structures. There was no postoperative vocal cord palsy due to recurrent laryngeal nerve injury. However, two patients developed transient hypoparathyroidism, which resolved in the end without the need for calcium or vitamin D supplementation after certain period of medical management (Table 3). Also, there was no incidence of postoperative hemorrhage or hematoma formation, although a single patient developed a postoperative seroma on postoperative day 9, which was managed conservatively without the need for further surgical intervention. On average, the wound catheter was removed 6.8 ± 1 days after surgery and the patient was discharged from the hospital at an average 11 ± 2.8 days from admission (Table 1). Final surgical pathology confirmed the diagnosis of papillary carcinoma for every patient. The total number of cervical nodes retrieved from CCND and MRND was 9.8 ± 4 and 33.1 ± 11 respectively, and the number of positive metastatic nodes was 3 ± 1.4 and 7.3 ± 1.7 respectively (Table 1). In three patients (patients 2, 3, and 4), the presence of one parathyroid gland was each verified in the pathology specimen. All four patients have received high-dose (150 mCi) radioiodine ablation (RAI) therapy after the operation and are being followed up (average 11.3 months, range 9–13 months) on a regular basis with no evidence of recurrence (post-RAI, most recent, nonsuppressed thyroglobulin range 0.1–0.4 ng/ml, antithyroglobulin antibody range 13.7–147.5 IU/ml).

Table 2 Operation times for the patients

Table 3 Postoperative complications

Discussion

Robotic total thyroidectomy and MRND via unilateral RA approach without axillary incision was technically feasible. This integrates the surgical technique of robotic facelift thyroidectomy as described by Terris et al. and the surgical technique of RAND via a MFL or RA approach as reported by our institution. Appropriate positioning of the patient and configuration of the robotic arms are keys to successful operation. When performing the thyroidectomy, the surgical procedure could be greatly facilitated if the patient’s neck is relaxed from previous status of neck extension for RAND. Also, during the process of contralateral thyroidectomy, it is considered important that the patient should be tilted or rotated 15–30° towards the surgeon (ipsilateral downwards, contralateral upwards) at the patient’s table for optimal exposure. The SCM muscle should be retracted posteriorly and inferiorly with a retractor to improve the surgical view from the console. It is essential for the assistant to push down the trachea with the suction tip to facilitate the robotic dissection. The Maryland dissector forceps may be changed to ProGrasp forceps to enhance handling of the thyroid gland tissue. It is important that sufficient working space must be created for comfortable movements of the robotic arms through the RA port during both total thyroidectomy and neck dissection. As can be recognized from the general clinical information of the patients (Table 1), the size of the thyroid carcinoma and the BMI affects little in performing the operation via this particular approach.

The greatest initial advantage offered by this operative procedure would be of cosmetic value. In comparison with conventional transcervical open methods, by placing the surgical incision behind the auricle and within the hairline, an obvious cervical incision would be completely eliminated, however, at the cost of more extensive dissections just like any other remote access surgical techniques. Among other approach methods of remote access surgery, this specific operative procedure is thought to be superior. It would gain easier access to the lymph node basin of the upper neck than when TA approach is adopted and as Terris et al. have previously reported, the area of dissection required would be 38 % lesser than the TA approach, making it a less invasive technique.9 In our earlier periods, we have utilized the transaxillary and retroauricular (TARA) approach for MRND with or without thyroidectomy, but after accumulation of surgical experiences, the operation could be managed with a single RA approach, thereby minimizing the extent of invasiveness.17 Also, from the head and neck surgeon’s point of view, the operation would be more comfortable due to familiar local anatomical structures, easier to address the spinal accessory nerve, and the thyroid gland and lymph node tissues at the central neck could be easily reached due to the decreased area of dissection compared with the TA. The risk of intraoperative brachial plexus injury or any other physical sequelae resulting from the specific positioning of the patient for TA approach would be avoided and incidence of postoperative lymphedema commonly resulting from long transcervical operation scars could be decreased with this technique.

This operative procedure, however, has a disadvantage of longer operation times. It is contemplated that the operation time would be significantly decreased through accumulation of surgical experience. This is a clinical report of our successful yet initial surgical experiences of robotic total thyroidectomy and RAND via single RA port. Despite our promising operative results, an expanded population from careful selection of eligible patients is mandatory, and future prospective trials should be conducted to evaluate long-term outcomes and to overcome potential limitations.